Everybody involved knows the NFC West will likely come down to these two nemeses when this season’s all said and done, with a pair of dynamic young quarterbacks leading the way. The 49ers have captured the last two division titles, after Seattle won in 2010 with a losing record.

The Seahawks are miffed at Harbaugh for several things.

They claim he honked his horn at their team bus leaving Candlestick Park after San Francisco’s win last October. Safety Earl Thomas insists that will only serve as fuel, along with all of the other jabs from both sides in recent months.

At least some Seattle players considered the move as mockery. Harbaugh has denied the honk, calling it a “fabrication.”

“Of course we’d take it that way,” Thomas said. “When you carry yourself like a champion on and off the field, good stuff is going to happen for you. ... It just seems like he has a lot of personality, that’s all fun and games. It’s good for the sport of football. He’s a competitor it seems like. Our coach is the same way. I don’t think our coach would do that.”

This budding rivalry between San Francisco and Seattle has intrigue on so many levels. And it appears to have staying power, too, as long as Carroll and Harbaugh keep winning and keep their jobs.

The coaches certainly provide plenty of entertainment value.

“It is a fun thing to look at,” Thomas said. “As a competitive standpoint, you definitely look at it as, OK, I know in their minds — they probably won’t say it in front of their players — but they definitely want to win this game a lot more than other games. That just adds a cherry on top to the excitement building up to this game.”